Interpretive Summary: Collar rot of lentil is caused by the fungal pathogen Sclerotium rolfsii. It is generally a warm weather disease. The pathogen survives in soil and can infect a wide range of crops causing damping-off and stem rot. Resistant cultivars are available. This chapter provides descriptions of the disease symptoms, disease cycle, and management practices.

Technical Abstract:
Collar rot of lentil is an important seedling disease particularly under high moisture and high temperature conditions. It is caused by the fungal pathogen Sclerotium rolfsii. The pathogen has an extremely wide host range, and produces sclerotia, which can survive in the soil for many years. Infected young seedlings show damping-off symptoms. Plants infected at an advanced stage gradually turn pale, droop and dry. Although its symptoms are similar to Sclerotinia white mold, it can be differentiated by its cord-like mycelial strand and smaller sized sclerotia. It occurs under warm weather, whereas Sclerotinia disease occurs under cool weather conditions. Control practices include a combination of cultural, biological and chemical methods. Resistant cultivars are available.